Conventional switching systems may use 10G Form Factor Pluggable standard interface (XFI) or 10G Attachment Unit Interface (XAUI) as a system interface mode between a physical layer (PHY) and a media access control (MAC) layer. XFI and XAUI may provide support for 10G line speed. Serial Gigabit Media Independent Interface (SGMII) and Quad SGMII (QSGMII) interfaces may be used to support 10/100/1000 Mbit/s switching.
Switching systems employing MultiGig capability may provide for transmitting data varying between multiple variable rates, such as 100M, 1G, 2.5G, 5G, and 10G. This has created a need for system interfaces to support all the line speeds seamlessly. Multigig PHYs and other conventional network devices may not support all the line speeds in a single system interface mode such as XFI, XAUI, SGMII, and QSGMII. This may result in the line-side going down to accommodate a switching instruction.
Some prior line cards, such as 4K line cards may employ Small-form Factor Pluggable (SFP) optic modules to change a system interface mode between MAC and PHY devices based on whether the SFP is set to 1G or 10G. However, such prior line cards do not provide line-side auto-negotiation. Such approaches do not work with copper lines, as the line-side must remain up during the system interface mode change.